// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

// Originally written by Alf Nielsen, re-written by Michael Zhou
(function(mod) {
  if (typeof exports == 'object' && typeof module == 'object')
    // CommonJS
    mod(require('../../lib/codemirror'));
  else if (typeof define == 'function' && define.amd)
    // AMD
    define(['../../lib/codemirror'], mod);
  // Plain browser env
  else mod(CodeMirror);
})(function(CodeMirror) {
  'use strict';

  function words(str) {
    var obj = {},
      words = str.split(',');
    for (var i = 0; i < words.length; ++i) {
      var allCaps = words[i].toUpperCase();
      var firstCap = words[i].charAt(0).toUpperCase() + words[i].slice(1);
      obj[words[i]] = true;
      obj[allCaps] = true;
      obj[firstCap] = true;
    }
    return obj;
  }

  function metaHook(stream) {
    stream.eatWhile(/[\w\$_]/);
    return 'meta';
  }

  CodeMirror.defineMode('vhdl', function(config, parserConfig) {
    var indentUnit = config.indentUnit,
      atoms = parserConfig.atoms || words('null'),
      hooks = parserConfig.hooks || { '`': metaHook, $: metaHook },
      multiLineStrings = parserConfig.multiLineStrings;

    var keywords = words(
      'abs,access,after,alias,all,and,architecture,array,assert,attribute,begin,block,' +
        'body,buffer,bus,case,component,configuration,constant,disconnect,downto,else,elsif,end,end block,end case,' +
        'end component,end for,end generate,end if,end loop,end process,end record,end units,entity,exit,file,for,' +
        'function,generate,generic,generic map,group,guarded,if,impure,in,inertial,inout,is,label,library,linkage,' +
        'literal,loop,map,mod,nand,new,next,nor,null,of,on,open,or,others,out,package,package body,port,port map,' +
        'postponed,procedure,process,pure,range,record,register,reject,rem,report,return,rol,ror,select,severity,signal,' +
        'sla,sll,sra,srl,subtype,then,to,transport,type,unaffected,units,until,use,variable,wait,when,while,with,xnor,xor',
    );

    var blockKeywords = words(
      'architecture,entity,begin,case,port,else,elsif,end,for,function,if',
    );

    var isOperatorChar = /[&|~><!\)\(*#%@+\/=?\:;}{,\.\^\-\[\]]/;
    var curPunc;

    function tokenBase(stream, state) {
      var ch = stream.next();
      if (hooks[ch]) {
        var result = hooks[ch](stream, state);
        if (result !== false) return result;
      }
      if (ch == '"') {
        state.tokenize = tokenString2(ch);
        return state.tokenize(stream, state);
      }
      if (ch == "'") {
        state.tokenize = tokenString(ch);
        return state.tokenize(stream, state);
      }
      if (/[\[\]{}\(\),;\:\.]/.test(ch)) {
        curPunc = ch;
        return null;
      }
      if (/[\d']/.test(ch)) {
        stream.eatWhile(/[\w\.']/);
        return 'number';
      }
      if (ch == '-') {
        if (stream.eat('-')) {
          stream.skipToEnd();
          return 'comment';
        }
      }
      if (isOperatorChar.test(ch)) {
        stream.eatWhile(isOperatorChar);
        return 'operator';
      }
      stream.eatWhile(/[\w\$_]/);
      var cur = stream.current();
      if (keywords.propertyIsEnumerable(cur.toLowerCase())) {
        if (blockKeywords.propertyIsEnumerable(cur)) curPunc = 'newstatement';
        return 'keyword';
      }
      if (atoms.propertyIsEnumerable(cur)) return 'atom';
      return 'variable';
    }

    function tokenString(quote) {
      return function(stream, state) {
        var escaped = false,
          next,
          end = false;
        while ((next = stream.next()) != null) {
          if (next == quote && !escaped) {
            end = true;
            break;
          }
          escaped = !escaped && next == '--';
        }
        if (end || !(escaped || multiLineStrings)) state.tokenize = tokenBase;
        return 'string';
      };
    }
    function tokenString2(quote) {
      return function(stream, state) {
        var escaped = false,
          next,
          end = false;
        while ((next = stream.next()) != null) {
          if (next == quote && !escaped) {
            end = true;
            break;
          }
          escaped = !escaped && next == '--';
        }
        if (end || !(escaped || multiLineStrings)) state.tokenize = tokenBase;
        return 'string-2';
      };
    }

    function Context(indented, column, type, align, prev) {
      this.indented = indented;
      this.column = column;
      this.type = type;
      this.align = align;
      this.prev = prev;
    }
    function pushContext(state, col, type) {
      return (state.context = new Context(
        state.indented,
        col,
        type,
        null,
        state.context,
      ));
    }
    function popContext(state) {
      var t = state.context.type;
      if (t == ')' || t == ']' || t == '}')
        state.indented = state.context.indented;
      return (state.context = state.context.prev);
    }

    // Interface
    return {
      startState: function(basecolumn) {
        return {
          tokenize: null,
          context: new Context((basecolumn || 0) - indentUnit, 0, 'top', false),
          indented: 0,
          startOfLine: true,
        };
      },

      token: function(stream, state) {
        var ctx = state.context;
        if (stream.sol()) {
          if (ctx.align == null) ctx.align = false;
          state.indented = stream.indentation();
          state.startOfLine = true;
        }
        if (stream.eatSpace()) return null;
        curPunc = null;
        var style = (state.tokenize || tokenBase)(stream, state);
        if (style == 'comment' || style == 'meta') return style;
        if (ctx.align == null) ctx.align = true;

        if ((curPunc == ';' || curPunc == ':') && ctx.type == 'statement')
          popContext(state);
        else if (curPunc == '{') pushContext(state, stream.column(), '}');
        else if (curPunc == '[') pushContext(state, stream.column(), ']');
        else if (curPunc == '(') pushContext(state, stream.column(), ')');
        else if (curPunc == '}') {
          while (ctx.type == 'statement') ctx = popContext(state);
          if (ctx.type == '}') ctx = popContext(state);
          while (ctx.type == 'statement') ctx = popContext(state);
        } else if (curPunc == ctx.type) popContext(state);
        else if (
          ctx.type == '}' ||
          ctx.type == 'top' ||
          (ctx.type == 'statement' && curPunc == 'newstatement')
        )
          pushContext(state, stream.column(), 'statement');
        state.startOfLine = false;
        return style;
      },

      indent: function(state, textAfter) {
        if (state.tokenize != tokenBase && state.tokenize != null) return 0;
        var firstChar = textAfter && textAfter.charAt(0),
          ctx = state.context,
          closing = firstChar == ctx.type;
        if (ctx.type == 'statement')
          return ctx.indented + (firstChar == '{' ? 0 : indentUnit);
        else if (ctx.align) return ctx.column + (closing ? 0 : 1);
        else return ctx.indented + (closing ? 0 : indentUnit);
      },

      electricChars: '{}',
    };
  });

  CodeMirror.defineMIME('text/x-vhdl', 'vhdl');
});
